JPS58133843A - Operating method of magnetic separator and its device - Google Patents

Abstract

PURPOSE:To make a separator compact and light, by promoting a rise of exciting current by applying an excessive exciting-voltage to an exciting coil at the time of starting the exciting, in the separtor which excites by detecting an inclusion of a magnetic piece. CONSTITUTION:When a magnetic piece, mixed in raw materials on a moving conveyor 19, passes through a detecting means 24, a detecting signal is inputted to a controlling device 30 to close changeover-means MC1-1-3, thereby an excessive exciting-voltage VH is supplied to an electromagnet of an electromagnetic separator 12. An exciting current flows in the electromagnet as shown by the dotted line to rapidly increase toward an excessive stationary-current IH corresponding to the voltage VH, and shows a rapid rise so as to attain a lower limit value IL of exciting current capable of attracting the magnetic piece, in an extremely short time t1. When the exciting current exceeds a current vaue IS corresponding to an ordinary exciting-voltage VS, an ordinrily closed contact and an opened contact at the MC-2 opens and closes respectively to change over the voltage supplied to the electromagnet to the ordinary exciting-voltage VS.

Description

[Detailed Description of the Invention] The present invention detects the presence of magnetic pieces (iron pieces, etc.) in the papermaking raw material using a magnetic piece detection means such as a metal detector, and uses this detection signal to excite the excitation coil of the magnetic separator. Regarding the operating method and operating device of a magnetic separation device that attracts and separates the magnetic pieces, in particular, the entire device can be made smaller and lighter;
A method of operating a magnetic separator of the type described above, which can be made smaller and lighter so that it can be mounted on a cart even in a narrow space such as the inside of an unloader rod used when unloading raw materials such as coal or ore from a ship, and the method thereof. Attire! It provides:

An unloader is used to unload raw materials such as coal and ore from ships. The raw materials unloaded by the A/C1-da are transported to the yard by a conveyor installed on the ground. At this time, if the egg material contains impurities from iron scraps, it may cause tears to the conveyor belt of the one-town conveyor or damage the conveyor mechanism, which may occur if 1.f.

The economic loss associated with this failure of the conveyor is L', which not only increases the ship's berth time but also has a significant impact on the 1111 system. Therefore, the magnetic pieces in the P material are required to be completely separated in the I-loader before the conveyor.

This problem can be solved by installing a magnetic separator at an appropriate location on the in-machine conveyor or i installed in the unloader to magnetically attract and separate the magnetic pieces.

On the other hand, for economical reasons such as improving the efficiency of unloading operations and shortening ship time, a vessel with an extremely high unloading capacity (1) is required. For this reason, F:j k7 is also a big plus for the magnetic separator that removes magnetic impurities mixed in the conveyed material! ability is required.

The processing capacity of this magnetic separator is determined by the suction power of the electromagnet, which is the main part, and the requirement for high suction power leads to the electromagnet becoming large.

On the other hand, existing unloaders do not have enough space to accommodate huge electromagnets or sufficient strength to support them, and even new unloaders do not have sufficient structural strength and capacity to accommodate them. If planned, it would inevitably lead to the unloader becoming larger, and it would be extremely difficult to implement it considering the changes in peripheral equipment and systems due to this enlargement.

For these reasons, it is desirable to make the electromagnet, which is the main part of the magnetic component, as small as possible to make the entire device smaller. However, there is a limit to miniaturization when considering the temperature rise of the electromagnet due to heat generated by the excitation coil.

Therefore, as a means of suppressing the temperature rise while maintaining the suction ability, it is possible to cool down the excitation coil, to excite it only when magnetic pieces are mixed, and to reduce the weight of the cart. Furthermore, it is conceivable that these two methods may be used together to further enhance the effect.

The method of energizing the electromagnet only when a magnetic piece is present, as described by Tsumugi, has the following problems when it is actually applied.

In other words, the electromagnets used in magnetic separators, which have a large attraction capacity, have an extremely large inductance.
This causes a significant delay in the start-up of the excitation current.
Therefore, there is a problem in that even if excitation is started immediately upon receiving a detection signal of the presence of magnetic pieces, the desired magnetic attraction force cannot be exerted immediately.

To solve this problem, it is necessary to take into account the time delay and the conveyor belt speed and make the distance between the magnetic piece detection means and the magnetic separator sufficiently large. (in-flight conveyor, etc.) must also be sufficiently long. This is because the time from when the presence of magnetic pieces is detected until the magnetic pieces reach the magnetic separator needs to be longer than the excitation current rise time.

However, in the inside of the unloader, which has a high-density structure, there is no room to secure such a swivel or to support a long internal conveyor with sufficient strength, and this is virtually impossible. Ta. .

The present invention was made to solve these problems in the conventional technology, and it is possible to make the magnetic separation device smaller and lighter, thereby making it possible to install it even in a narrow place such as the aforementioned unloader. An object of the present invention is to provide a method for operating a magnetic separation device and an apparatus for the same.

The present invention is characterized in that when a magnetic piece detection signal is emitted from the magnetic piece detection means, an excessive excitation voltage higher than the normal excitation voltage that can attract the magnetic piece is applied to the excitation coil to promote the rise of the excitation current. When the excitation current reaches a value that allows the magnetic piece to be attracted, it is detected or converted to a normal excitation voltage using a preset timer device, thereby reducing the delay in the start-up of the excitation current and reducing the size and weight of the device. The point is that it makes it possible.

That is, according to Akira Motonawa, JRK detects the presence of magnetic pieces in raw materials when magnetic pieces are mixed, and the magnetic separator uses this detection signal to energize the excitation coil of the magnetic separator to attract and separate the magnetic pieces. In the operating method, when a detection signal of mixed magnetic pieces is issued from the magnetic piece detection means, excitation of the excitation coil is started with an excessive excitation voltage higher than a normal excitation voltage capable of attracting a magnetic piece, and an excitation current is started. The magnetism is characterized in that the excessive excitation voltage is converted into the normal excitation voltage by detecting the excitation current after a predetermined dead period has elapsed or when the excitation current reaches a value capable of attracting the magnetic piece. A method of operating a separation device is provided.

According to another aspect of the present invention, there is provided an apparatus for carrying out the above-mentioned operating method, in which the magnetic piece detection means detects the presence of magnetic pieces in the raw material, and the detection signal causes the excitation coil of the magnetic separator to be activated. In an operating device for a magnetic separation device that attracts and separates the magnetic pieces by excitation, an excitation circuit is connected to a supply source of a normal excitation voltage capable of attracting the magnetic pieces and a supply source of an excessive excitation voltage that is larger than the normal excitation voltage; a first switch for switching the excitation circuit to apply the excessive excitation voltage to the excitation coil in response to a detection signal from the magnetic piece detection means;
and a snow collecting O switching means that switches the dynamic magnetic circuit to apply the normal excitation voltage to the excitation coil when the excitation current reaches a value that allows the magnetic piece to be attracted, or after a set predetermined period has elapsed. An apparatus for operating a magnetic separation device is provided.

Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram illustrating a schematic structure of an unloader suitable for applying the present invention, and a man trolley type unloader is illustrated.

The unloader is a rail 1 installed on land along the quay.
．． A pedestal 3.3 that can run on 1 via rolling wheels 2.2
and a crossbeam 4 that is supported by these pillars and extends to the sea, and the crossbeam 4 is equipped with a man trolley type crane hoisting device (hereinafter referred to as hoisting at) which can run via a trolley 17. ) 6 is deployed. A cradle 1 is provided at a height that does not interfere with the traveling of the hoisting device 6 of the aircraft S, and a receiving pedestal 8 is disposed near the sea-side end of the cradle. At the end there is a delivery hog-9 (
In the illustrated example, ``Gunyu'' is placed.

An in-machine conveyor 1° is installed which connects the receiving hole I-8 and the sending hole 9 within the frame 1. A raw material feeding device 11 in the unloader is constituted by the receiving hole #4g, the sending hole #9, and the in-machine conveyor IOK.

A magnetic separator 12 is installed in the middle of the in-machine conveyor 100, and the nuclear magnetic separator is equipped with an oil-filled electromagnet 13 (see FIGS. 2 and 3) that forms a lower 1tiK magnetic field. The horizontal magnetic separation 12 is supported by the frame 7 or the body of the in-machine conveyor 1G via a suitable support member, and is lowered onto the in-machine conveyor 10.

An insulating oil circulation device 14 is provided on the pedestal 7, and is configured to forcibly circulate cooling insulating oil into an oil tank in which the excitation coil of the magnetic dispersion machine 12 is immersed.

In addition, a feeder 1 is provided at the lower end of the receiving hole/mother 8.
5 is connected, and the raw material input into the receiving hot spring is supplied onto the in-machine conveyor 10 through this feeder 15. The delivery machine 1 is transported by the in-machine conveyor 1o! The raw materials to be input into 1 are supplied from these delivery hollers onto the above-ground conveyor y47111,1@, and sent to the yard by the core conveyor.

The hoisting device 6 is supported so as to be able to run along the horizontal ellipse 4 of the Toro 9tyK, and reciprocates between the sea side position indicated by the concentrated line in Fig. 1 and the land side position indicated by the two-dot chain line. It's getting wet. A raw material loading/unloading rack such as a grab bucket II is connected to the end of the rope of the hoisting device. Then, the raw materials on the berthed ship are scooped up in fixed amounts by the hoisting device 6, moved by the Toro I717 to the receiving hopper #-8, and then thrown into the receiving hopper and transferred to the feeder. t+S and is supplied to the in-machine conveyor 10 at a predetermined delivery speed. The raw material from the in-machine conveyor 10 is fed through a delivery hoop 9, 9 to a conveyor 16.1 and sent to the yard.

FIGS. 2 and 3 show an in-machine conveyor 10 and a magnetic separator 1 suitable for implementing the present invention! FIG. In FIGS. 2 and 3, parts corresponding to those in FIG. 1 described above are designated by the same reference numerals.

In FIGS. 2 and 3, an oil-filled electromagnet 13 having a magnetically active surface 20 on its lower surface to apply a magnetic field upward to the conveyor belt 19 of the 12 magnetically separated Ia machine conveyor 10 forms a nuclear magnetically active surface. The excitation coil is immersed in a tank of insulating oil.

Around the electromagnet 13, an endless belt 11 is stretched along the magnetically active surface 20 and rotates in the direction of the arrow in FIG. This endless belt consists of a driving pulley 22 and a driven pulley 2.
It is stretched along 3. The magnetic separator 12 having such a structure is suspended at an appropriate outer position in the middle of the in-machine conveyor 1G.

A magnetic piece detection means 24 such as a metal detector is installed at an intermediate position between the magnetic separator 12 and the feeder 15 of the inner ring conveyor 10, and detects the passage of magnetic pieces such as iron pieces on the conveyor belt 19. ing.

The insulating oil circulation device x4 installed on the pedestal 7 is a radiator! 6,
Consisting of an oil supply tube F26 and other fluid control elements (not shown), conduit 27,! 7, the electromagnet 131'C of the magnetic separator 12 is connected to the electromagnet 131'C of the magnetic separator 12, and the cooling insulating oil is forcibly circulated in the oil tank of the electromagnet.

A chute 28 is provided at the position after the conveyor belt 1 of the endless belt 1 passes through the magnetic surface 20 to remove the magnetic pieces that are attracted to the KM endless belt surface IFiK while passing through the magnetic action surface 20. ing. A second magnetic piece detection means 29, such as a metal detector, is disposed on the shoe 21, such as a metal detector, for confirming separation of magnetic pieces by the magnetic separator 1.

Magnetic piece detection means (hereinafter referred to as first magnetic piece detection means) 24 for detecting magnetic pieces on the conveyor belt 1 and a second magnetic piece detection means provided in the magnetic piece sending path from the magnetic separator 12. The means 29 are connected to a control device F30, which is connected to the electromagnet 13 of the magnetic separator 12. The control device also includes a DC power supply unit fl'f31.
Three types of excitation voltages are supplied from.

The control device 3G is for controlling the excitation voltage of the electromagnet 13, and starts excitation upon receiving a magnetic piece detection signal (S, in Fig. S) from the first magnetic piece detection means 24. And said 1st o @ sex piece detection hand Wj! It operates so as to receive the magnetic piece passage signal (8, in Figure S) from z* and end the excitation.

FIG. 4 is a diagram showing a control circuit within the control device 30.

In FIG. 4, the control circuit includes a supply source P of a normal excitation voltage V that can attract a magnetic piece (connected to one output of the DC power supply w31), and an excessive excitation voltage VTi that is larger than the normal excitation voltage. Source of p.

(connected to the other output of the DC power supply 31); a current detector 33 inserted into the excitation circuit to detect the excitation current value; and the first magnetic piece detection means. The excitation circuit 3! receives the detection signal S1 from the excitation circuit 3!24 and applies the excessive excitation voltage VH to the excitation coil! The first switching means Mol, Mo1-1, M
o1-2, MOl-3, when the excitation current reaches the value K that allows the magnetic piece to be attracted (step s in Fig. 2 (0)), the excessive excitation voltage VW is set by the detection signal from the current detection @aS. A second switching means 'MO2, Mo1-1 is provided for switching the excitation circuit S! so as to apply the normal excitation voltage V@K'' to the excitation coil.

Furthermore, the excitation circuit includes a second magnetic piece detection means as explained with reference to FIGS. 2 and 3! #@z magnetic piece detection means detects that the magnetic piece attracted and separated from the raw material has passed through the delivery path, and the excitation current of the excitation circuit 32 is controlled by the detection signal 82. It is configured to shut off and always return to 1111'c. This detection signal s2 causes the first and third switching means (
(usually composed of a switching electromagnetic contactor) 24, the goose 1 is completely returned to its original state 111COFF state 111)K, and becomes the state 11 awaiting the detection of the next magnetic piece.

The current detector 33 is the excitation circuit 3! a current sensor 08 inserted in series with the excitation current of the current sensor 08, a voltage/quantity regulator 34 that compares the current value signal voltage 1 from the current sensor with a reference voltage layer, and the second switching means (magnetic contactor). Operation coil MO! When the current value signal l from the current sensor aS exceeds the reference voltage ICs, the second switching means MO snow contact M
It operates to switch 02-1. That is, contact M
It operates to open the normally closed contact of O2-1 and close the normally open contact.

In addition, if extremely high precision is not required for the excitation voltage control accuracy, the above switching operation may be configured to be performed only by a switching means such as a current relay directly incorporated in the excitation circuit 32. is also possible.

Next, the operation of the magnetic separation device will be explained with reference to FIG. A detection signal S1 shown in FIG. When the signal 81 is applied to the control device 10, the contacts MCl-1 and Jio 1-2 of the first switching means are switched from the normal state shown in FIG.
, MO1-3 are closed, and the excessive excitation voltage MAH at the terminal P is supplied to the electromagnet 13.

An excitation current of 6, as shown by the dotted line in Figure 3 (0), flows through the electromagnet 13 and rapidly increases toward the excessive steady-state electric current fi1m corresponding to the excessive excitation voltage Vm (Figure S (B)). . That is, it shows a rapid rise that reaches the lower limit value of the excitation current that can attract the magnetic piece in a very short time t1.

When the excitation current exceeds the current value corresponding to the normal excitation voltage V's K, the output signal of the current sensor O8! exceeds the reference voltage g= set corresponding to the current value knee, the above-mentioned
The output of the 4-lator s4 passes through the driver 36 to the relay 3g.
is activated, and the contact MO2-1 of the twenty-sixth switching means is switched. That is, the normally closed contact of MO2-1 in FIG. , switches to .

The purpose of applying the excessive excitation voltage VW at the initial stage of excitation is to speed up the initial rise of the excitation current and shorten the time t1 required to reach a current value that can attract the magnetic piece.

In other words, if the initial excessive excitation voltage VW is not used and only the normal excitation voltage V- is applied to the middle, the excitation current will be
As shown by the dotted line in Figure (0), the current rises toward the normal steady current 8 corresponding to the voltage V-, so its rise is delayed, and the time it takes to reach the lower limit value ILK that can be attracted is 1. As shown, it becomes long.

To give a specific numerical example, when using a conveyor with a belt width of i and am and operating at a conveyance speed of 'tomZ minutes for ore and xaom1 minute for coal, the electromagnet specifications were as follows. .

Excessive excitation voltage V is DC620''/ and excitation time t.

is 1 second, and the normal excitation voltage is DoBMO"1. Also, the values of the steady excitation current corresponding to these excitation voltages are Il' = 1211 and zs = = lot, and the power is Nine at 80 KW and 35.!IKW respectively.

The rise time when no excessive excitation voltage is applied is approximately 7 seconds, and in this specific example, this was achieved by shortening this to t1 = 1 second.

According to the present invention, since the excessive excitation voltage vH is initially applied, the rise time until reaching the attractable current value is greatly shortened. The interval can be reduced, and the magnetic separation device can be made smaller and lighter. Excessive excitation voltage V
, is applied only for the initial necessary minimum time, so power is not wasted and the energy saving effect is excellent.

In this way, the electromagnet 13 is energized to attract and remove the magnetic pieces in the raw material, and the raw material is removed onto the chute 28.

When the removed magnetic piece passes through the magnetic piece detection means 211 of tP,2 on the chute 28, each contact Me1-1, Mo1- of the first switching means is activated by the detection signal B2.
3. MO1-3 is opened and excitation of the electromagnet 13 is completed. The extinction of the excitation voltage and excitation current at this time is shown in Figure S (A
), (B), (0)K have the characteristics as shown in the example. After the excitation ends and the body dies, it is necessary to wait for the arrival of the next magnetic piece.

In the above embodiment, the period of application of the over-excitation Wt current at the initial stage of excitation is the period from detecting the current value on the way to rising until it reaches the steady current X, K corresponding to the normal excitation voltage, and at the time of Although the configuration is such that the excitation voltage is switched to the normal excitation voltage, this may be done by setting the excessive excitation voltage application period to a predetermined period using a timer or the like in accordance with the rise characteristics of the excitation coil.

In addition, in the above embodiment, excitation is terminated by the detection signal all from the second magnetic piece detection means 2g (this is also the same as setting the application time of the excessive excitation voltage using a timer or the like). It is also possible to set the timing, etc.

Furthermore, the magnetic separator 12 is equipped with a suspended type electromagnet having an evacuation mechanism using an endless belt 21, but it is possible to use other types of electromagnets depending on the structure, unloading capacity, or mounting location of the unloader. It is also possible to create a magnetic separator with an electromagnet. For example, this can be done by installing a rotating drum-shaped magnetic separation hole at the exit of the receiving hole/8, or by attaching an electromagnetic device to the terminal pulley of the in-machine conveyor 10.

As is clear from the above explanation, according to the present invention, the mixed magnetic piece detection means and magnetic The distance between the separator and the separator can be reduced,
As a result, it is possible to obtain a method and apparatus for operating a magnetic separation apparatus, which allows the apparatus to be made smaller and lighter, and which can be easily mounted in a narrow space, such as in an unloader.

[Brief explanation of the drawing]

FIG. 1 is an explanatory view illustrating the overall structure of an unlogu equipped with a magnetic separation device suitable for applying the present invention, FIG. 2 is a schematic explanatory view showing an embodiment of the present invention, and FIG. An explanatory diagram showing a cross section along the line 1-IK in the figure, FIG. 4 is a circuit diagram illustrating the electric circuit configuration of a magnetic separation device control device according to an embodiment of the present invention, and FIG. 5 is an operating method according to the present invention. This is a graph illustrating. 5... Machine at unloading end, 7... Frame, 8... Receiving hole/tar, 9... Sending hole/#-+, l Q... In-machine conveyor, 12... Magnetic Separator, 13... Electromagnet, 19... Conveyor belt, 20... Magnetic action surface, 21... Endless belt, 24... First magnetic piece detection means, 28... Chute, 29 ...Second magnetic piece detection means, 30...Control device, 31...DC power supply device, (2...Excitation circuit, 33...Current detection circuit, MO・1...First MC2...Second switching means, 81, B!...Magnetic piece detection signal, vH...Excessive excitation voltage, v,...Normal excitation voltage, I,...Excessive Steady excitation current, Engineering 8... Normal steady excitation current, 1, %1... Rise time. Agent Tatsuyuki Unuma (and 2 others) 4th Shi I \33 No. 51. = + Oaza, Ueda City 1111 Uedawara

Claims (1)

[Claims] (Seal) A magnetic piece detecting means detects the presence of magnetic pieces in the raw material, and the detection signal excites the M++ magnetic coil of the second magnetic separator to attract and separate the magnetic pieces. In the operating method of the separation device, when a detection signal of mixed magnetic pieces is issued from the magnetic piece detection means, an excessive excitation voltage that is larger than a normal excitation voltage that can attract magnetic pieces for a predetermined period is applied to the excitation coil to excite it. 1. A method of operating a magnetic separator, comprising promoting the rise of a current, and then switching to the normal excitation voltage. (2) The carp detects when the excitation current reaches a value that allows the magnetic piece to be attracted, and the excessive excitation voltage is switched to the normal excitation voltage by the detection signal of (7). ) Method of operating the magnetic separation device described in section 2. (1) A first 1ci magnetic piece detection means is provided in the sending path of the magnetic pieces separated by suction from the raw material, and the excitation of the excitation coil of the magnetic separator is terminated by the magnetic piece passage signal from the cough detection means. Claim No. 1 (1) characterized by
) or (2). (4) In the operation device of the magnetic separator, which detects the presence of magnetic pieces in the raw material by means of a magnetic piece detection means, and uses this detection signal to excite the excitation coil of the magnetic separator to attract and separate the magnetic pieces. An excitation circuit connected to a supply source of an attractable normal excitation voltage and an excessive excitation voltage greater than the normal excitation voltage, and applying the excessive excitation voltage to the excitation coil in response to a detection signal from the magnetic piece detection means. +41 switching means for switching the excitation circuit so as to switch the excitation circuit, and a second switching means operated by a timer to switch the excessive excitation voltage to the normal excitation voltage after a predetermined time has elapsed from the start of excitation. Driving device. (+5) Provided in the delivery path of the magnetic piece separated by attraction from the raw material and electrically connected to the excitation circuit h, ft
Claim 14, comprising: a second magnetic piece detection means; and means for switching the excitation circuit so as to terminate the excitation when a magnetic piece passing signal is emitted from the second magnetic piece detection means. ) Operating device for the magnetic separation device described in item 2. 141 @1 The presence of magnetic particles in the raw material is detected by the magnetic particle detection means, and this detection signal is used to control the magnetic separator's meter.
j Excite the magnetic coil to attract and separate the magnetic pieces. A. In the operation device of the magnetic separation device, a supply source of normal excitation voltage capable of attracting the magnetic pieces and a normal excitation voltage f (more than A magnetic circuit connected to a voltage supply source, a current detector inserted into the excitation circuit to detect the excitation current value, and the magnetic piece detection means. a first switching means for switching the magnetic circuit to apply a voltage to the excitation coil; and a first switching means for switching the magnetic circuit to apply a voltage to the excitation coil; a second switching means for switching the force magnetic circuit forward so as to apply the force to the excitation coil; (7) A second magnetic piece provided in the delivery path of the magnetic pieces separated by attraction from the raw material and electrically connected to the excitation circuit.
and third switching means for switching the excitation circuit to disconnect the excitation when a magnetic piece passing signal is issued from the second magnetic piece detection means. Operating equipment of the magnetic separation device described in Section Zheng (6)! .